Nanoparticulate Perovskites for Photocatalytic Water Reduction

SrTiO(3) and BaTiO(3) nanoparticles (NPs) were activated using H(2)O(2) or aqueous HNO(3), and pristine and activated NPs were functionalized with a 2,2′-bipyridine phosphonic acid anchoring ligand (1), followed by reaction with RuCl(3)(.)3H(2)O and bpy, RhCl(3)(.)3H(2)O and bpy, or RuCl(3)(.)3H(2)O. The surface-bound metal complex functionalized NPs were used for the photogeneration of H(2) from water, and their activity was compared to related systems using TiO(2) NPs. The role of pH during surface complexation was found to be important. The NPs were characterized using Fourier transform infrared (FTIR) and solid-state absorption spectroscopies, thermogravimetric analysis mass spectrometry (TGA-MS), and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), and the dihydrogen generation was analyzed using gas chromatography–mass spectrometry (GC-MS). Our findings indicate that extensively functionalized SrTiO(3) or BaTiO(3) NPs may perform better than TiO(2) NPs for water reduction.